Cordless telephone

The plug wires were the problem. The jeep runs so unbelievably smooth now.

RocketMouse

I've wrenched for a long time... some may argue the flip side of this...but....
When I do a sparkplug change (most vehicles I've done them on that means these wires have been firing current through them every few milliseconds for on average the last 70,000 miles...give or take... wires, cap, rotor are super cheap on our old Jeeps so when I did mine, I just called it good insurance to do the whole deal and call it a day. Just my 2 cents...

awg

I am weirdly the opposite way around, and never change wires until I have an issue, which is almost always never..if I see the plastic is brittle or cracking on a 30+yr old vehicle then yes

think I may have only ever actually changed wires once that were causing a misfire, more times just to make the engine bay look better

Not recommended, but its worked for me, I have no idea how long the wires have been on my DD, but it would be a long time, they are original style, did put in new plugs when I got it

Cordless telephone

About a week ago i calculated my mileage to 17 MPG but since I've changed the distributor cap and wires, i wonder if I've gained any?

cruiser54

Factory recommended interval was 30,000 miles for cap, rotor, plugs. 60,000 on wires.

At the dealership we started replacing the wires also at 30,000 because they were failing before 60,000 in the Arizona climate and having been "handled" during the 30,000 mile service. No extra labor charge, wires were cheap, and customers were happy,.

Cordless telephone

I believe they were changed only once in the Jeep's entire life. Considering it's at 160k miles and the damage to the cap and wires.

Idunno

If I change a cap because of the erosion of the contacts it's a fair use of logic to go the distance. To me that means replacing plugs to rotor and everything between.

When you pull the wires off the plugs you exert a pulling tension on the actual conductor that's terminated to the circular spark plug clip in the wire boot end. You can't avoid that because there's no provision in the construction of the boot ends that imparts the pulling force to only the circular clip, avoiding pulling stress on the conductor itself. Wires are cheap, in the overall scheme of things.

Another physical deterioration that occurs is one where conductors will only conduct for a certain period of time well enough to pass the kind of current needed for a particular spark heat. Electrons in a conductor are eventually depleted and, after a certain period of time, begin to actually resist the full current needed for proper spark. Extend that to the battery cables. Electricity flows negative to positive (electrons are negative) so electrical problem solving should begin with inspecting for known good battery cables. It's usually the negative cable that goes first. I'm replacing them on my 96 tomorrow and will follow-up with my 98 next weekend. Making sure that the terminals are clean and have good contact is essential but don't rule out the idea that the cable itself may well be electron depleted (won't pass high current). I've seen it first hand when trying to jump a friend's car. The negative cable outer insulation jacket began to smoke. He was having trouble keeping a battery in his car and the reason for that was a bad negative cable.

Again, cables are cheap but people don't usually consider them inclusive of normal maintenance habits.

cpttuna

Just my $.02 . I can tell the difference when I get the tires rotated. I can tell the difference when I change the oil. I can tell the difference when I change the plugs, wires and cap and rotor. Many don't change things until they have problems. To each his or her own. It costs to maintain a vehicle. I include a lot of things in regular maintenance and change things accordingly. That is the way I am. I also keep a record. Many on this forum do not keep record and have no idea when certain maintenance was done on their jeep, if it was ever done.

Cordless telephone

with it being my first car, im still learning my way around it. I've also kept a build thread of my jeep constantly updated with whatever i do/fix on it. Also have a list of my mileage every month. Thankfully problems have been popping up less often than when I bought her.